In 1972, Craig & Gary Cook (the “Cook Brothers”) started making BMX forks and frames using chrome-moly tubing. A longer version of the fork became popular on Southern California beach cruisers as an aftermarket accessory. By adding a brake tab for the English drum Brake, this same fork became a Marin County Mountain Bike Fork.
Their three-piece sealed bearing hubs were also redesigned for mountain bike use. Larger bearings and axles were installed to make them more suitable for the six-speed clusters, popular at the time.
Some of the local Southern California riders were using the Cook Brother’s beach cruiser frames for mountain biking so they modified the design by popular demand, using thicker dropouts derailleur hangers, sealed bottom brackets, cantilevered brakes and cable guides. The Brothers named this bike appropriately “ THE ALPINE”.